University Of Arizona Testing Sewage To Help Prevent Possible Coronavirus Outbreaks

By Scott Bourque
Published: Friday, August 28, 2020 - 1:35pm

What if there was a way to test large populations of people for the coronavirus, without needing nasal swabs or lab workers or expensive and scarce protective equipment?

The University of Arizona is developing a way to test wastewater to identify potential coronavirus hotspots. Researchers are testing sewage from multiple buildings on campus — if there are any virus particles in the sewage, then everybody who works in the building is tested individually for the virus.

Professor Ian Pepper is leading the testing program, which has already seen promising results after identifying the virus in sewage collected from a dormitory. Researchers found coronavirus in a sample of sewage collected from a residence hall. They quickly tested everybody in the building.

“The U of A team reacted, implemented testing the students, finding the two individuals that were positive," Pepper said. "By the way they were asymptomatic, and they would not have been found for quite some time following that. It really was a wonderful success story.”

After the two students were isolated, there was no virus found in the wastewater from that building the next day.

Pepper believes this can be scaled up to test larger communities. Public health researchers have used wastewater epidemiology to track Ebola outbreaks and see what drugs are prevalent in a particular community.

“The results of the test answers the question, is the virus in the defined community," Pepper said. "If the answer is yes, the concentration of the virus gives an indication of the severity of the pandemic and correlates with the number of infections.”

On the University of Arizona campus, Pepper says they typically collect samples from 20 building around campus around 8:30 a.m., and results are available around 5 p.m., giving health officials a way to test entire buildings for the virus in a single sweep.

"From one test, we get the prevalence in the virus in the whole community," he said. "The virus shed by individuals happens seven days prior to visible symptoms. So you have seven precious days in which you can undergo intervention. It's particularly useful for detecting the onset of a pandemic."

Pepper's team is also investigating large-scale samples of wastewater from municipal water treatment plants. So far, he says they've had great success detecting viral loads in communities of hundreds of thousands of people.

"We could clearly see the influence of the stay-at-home intervention when virus concentrations decreased, and opening up when virus concentrations increased," Pepper said.

Research still needs to be conducted on how sensitive these tests can be. Previous research found that one person infected with the polio virus could be detected in a sample of wastewater from a community of about 1,000 people.

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